1. Field of the Invention
This invention relates to the continuous melting of ferrous scrap metal and chromite in a submerged arc furnace to obtain a chromium containing iron suitable for the production of stainless steel, alloy steel or alloy cast iron.
2. Description of the Prior Art
The use of electric furnaces for melting scrap and producing iron is known. U.S. Pat. Nos. 3,665,085 issued May 23, 1972 and 4,423,514 issued Dec. 27, 1983 both teach a continuous process for melting scrap iron in an electric arc furnace. In both the '085 and '514 patents, the electrode is positioned above the molten material in the furnace and the charge to the furnace is scrap metal only. U.S. Pat. No. 4,119,454 issued Oct. 10, 1978 also teaches the use of an electric arc furnace for melting scrap. However, the electrode in the '454 patent is positioned in the molten material. In all three U.S. patents scrap metal is the only charge to the furnace.
Submerged arc furnaces are conventionally used for the manufacture of ferroalloys, phosphorus, silicon metal, calcium carbide and pig iron, and for the production of matte of copper, nickel and the platinum group elements. Typically, such submerged arc furnaces use either self-baking S.o slashed.derberg electrodes or prebaked electrodes. Submerged arc furnaces have been used in the past to produce silvery pig iron (iron containing typically 10-20% silicon) using a high percentage of scrap charged to the furnace.